IIRC there is some evidence of hormonal changes related to some volatiles associated with certain types of plastics. That might have something to do with it. But Obesity can also easily be explained by more mundane things like terrible diet and lifestyle and there's a huge body of evidence to show that if you change those, you lose weight.
>So I don't think we know enough to say confidently that people aren't just dropping dead inexplicably.
Well proving a negative is impossible. Further research into the potential health effects is needed. But at this stage I think worrying over every report that we found plastic in more and more places isn't cause for alarm until we actually know its dangerous.